Liquid crystal polymers are recognized as having great potential for the development of new materials with exceptional physical and mechanical properties. In general, liquid crystal polymers consist of polymer chains containing anisotropic structural units (mesogenic groups) which may be incorporated into the polymer backbone, as pendent groups, or both. The mesogenic groups may be rod-like or disc-like in nature. Fibers, films, and molded plastics processed from the liquid crystalline state have shown outstanding properties.
Another desirable characteristic of such liquid crystalline polymers would be that they be thermosetting. Liquid crystal thermosetting polymers are known, e.g., the acrylic-terminated thermoset resins and precursors disclosed by Conciatorri et al. in U.S. Pat. Nos. 4,440,945, 4,452,993, and 4,514,553, the epoxy-terminated thermoset resins and precursors disclosed by Muller et al. in U.S. Pat. No. 4,764,581, the various difunctionally terminated materials disclosed by Dhein et al. in U.S. Pat. No. 4,762,901.
Other thermosetting resins utilizing end groups such as maleimide, nadimide, methyl nadimide, and acetylenic are described in various patents such as U.S. Pat. Nos. 4,225,497, 4,550,177, 4,739,030, 4,661,604, 4,684,714, 4,851,495, 4,851,501, 5,114,612, 5,198,551, and 5,315,011.
Bis- or di-propargyl containing materials are known. (See, e.g., U.S. Pat. No. 4,226,800 to Picklesimer, U.S. Pat. No. 5,096,987 to Pigneri, U.S. Pat. No. 5,250,742 to Kohler et al., U.S. Pat. No. 4,885,403 to Inbasekaren and U.S. Pat. No. 5,155,196 to Kolb et al.). However, no liquid crystalline materials including bis- or di-propargyl groups are described in these patents.
It is an object of this invention to provide curable materials containing bis-propargyl endcaps. It is another object of this invention to provide curable liquid crystal materials containing bis-propargyl endcaps.
Another object of this invention is to provide thermoset bis-propargyl linked compositions including thermoset liquid crystal bis-propargyl linked compositions.